Mark Sanford, who lost his primary to a pro-Trump insurgent, warned the president's style was making the GOP the "party of Donald Trump."

The Republican lawmaker and former governor said his party was "playing with fire" by giving into the president's "cult of personality."

Rep. Mark Sanford, R-S.C.

Bill Clark | CQ Roll Call | Getty Images

South Carolina GOP Congressman Mark Sanford, who lost a primary to a conservative insurgent backed by President Donald Trump, warned on about the president’s ‘autocratic style’ that was eroding political discourse.

In a broad panel discussion on Saturday at New York’s Ozy Fest, Sanford broke down several of the reasons why he was defeated by Katie Arrington in June’s primary for South Carolina’s First District.

“The beauty of the American political experiment is we can agree to disagree. You might have a very liberal perspective, I might have a conservative perspective, but we can sit at the table and begin to hash out ideas,” Sanford said.

“The danger I believe of Donald Trump is he is autocratic in style, " said Sanford, who's been a frequent critic of Trump. That tendency "is not conducive to the open debate of ideas which has been the hallmark of Americans,” he added.

Sanford is a former governor who was once speculated as a potential presidential contender, but resigned in scandal after admitting to an extramarital affair. He then revived his political career with a successful bid for Congress.

That came to a screeching halt after Trump backed Arrington, an unapologetic defender of the president.

“He went after me in my primary and I lost my primary,” Sanford said on Saturday. “During her victory celebration, [Arrington’s] words were, ‘We are the party of Donald Trump’ and I could not disagree” more, Sanford said.

He added that the Republican party risks turning itself into a “a cult of a personality” based on Trump. “Our Founding Fathers were so deliberate in forming a nation of laws and not men, and if we go against that in the slightest form, we are playing with fire,” Sanford added.

Sanford noted that with a deficit of more than $1 trillion, the U.S. is flirting with a new financial crisis that Trump may not be able to manage.

“Trump is an economist populist. Telling you what you want you want to hear and selling a lie that he knows can’t come true,” Sanford added.

Trump has courted controversy with his base by stoking trade wars with most of the U.S.’s most important economic allies. People ostensibly aligned politically with the president have expressed concerns about how the multi-pronged dispute will affect their livelihoods, which include vast swaths of ranchers, farmers and whisky makers.

Grover Norquist, founder and President of Americans for Tax Reform who was also on the panel Saturday, weighed in on the subject of global tariffs.

“Tariffs are simply taxes. There not something special or different they are just stupid and destructive taxes on the American consumer,” said the GOP activist. “When we put up tariffs we hurt Americans.”

Rachel and Amanda Wylie, two sisters who attended the OZY discussion, largely agreed with Norquist.

"Is it worth that trade off for corporations to benefit and not the American people to benefit? In my opinion it’s not,” Rachel Wylie said.

“Its a target against our own people and what we are able to contribute into our economy while diminishing the relationships that we have had for decades and centuries with countries like Canada, UK and other places in Europe. As relationships disintegrate, this makes it easier for our enemies to get into our system here in the U.S,” she added.